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comparison Renderer/Engine/TextureHash.cc @ 539:3bc98f6d31ff draft

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Reorganization..
author Shinji KONO <kono@ie.u-ryukyu.ac.jp>
date Mon, 12 Oct 2009 09:39:35 +0900
parents
children 20f09564c586
comparison
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538:5641d121818e 539:3bc98f6d31ff
1 #include <string.h>
2 #include <stdlib.h>
3 #include "TextureHash.h"
4
5 static int id_count;
6
7 TextureHash::TextureHash(void)
8 {
9 table = (hashtable*)malloc(sizeof(hashtable)*TABLE_SIZE);
10
11 for (int i = 0; i < TABLE_SIZE; i++) {
12 table[i].tx_id = -1;
13 table[i].key = NULL;
14 }
15 }
16
17 TextureHash::~TextureHash(void)
18 {
19 free(table);
20 }
21
22 int
23 TextureHash::hash_function(const char *key)
24 {
25 //float value = 0.0;
26 int value = 0;
27
28 for (int i = 0; key[i]; i++) {
29 value += key[i]*(i+1)*17+1;
30 }
31
32 return value%TABLE_SIZE;
33 }
34
35 int
36 TextureHash::hash_regist(const char* key, int &id)
37 {
38 int hash = hash_function(key);
39
40 for (int i = 0; ; i++) {
41 if (table[hash].tx_id == -1) {
42 table[hash].key = (char*)key;
43 id = id_count++;
44 return 0;
45
46 } else if (strcmp(key, table[hash].key) == 0
47 && table[hash].tx_id != -1){
48 id = table[hash].tx_id;
49 return 1;
50 }
51 hash = ((37*hash)^(11*i)) % TABLE_SIZE;
52 }
53 }